JP5070825B2 - Mobile body equipped with a fuel cell - Google Patents

Description

  The present invention relates to a moving body equipped with a fuel cell, and more particularly to a technique for discharging a discharged fluid discharged from a fuel cell to the outside of the moving body.

  Conventionally, vehicles equipped with fuel cells have been developed. This vehicle travels by driving a motor with electric power generated by a fuel cell and rotating axles and wheels with the power. Such a vehicle is provided with a discharge pipe for discharging exhaust gas discharged from the fuel cell to the outside of the vehicle, and a discharge port, and this discharge port normally drives an internal combustion engine (engine). As in the case of the vehicle that travels, the vehicle is disposed in the lower floor behind the vehicle body (see, for example, Patent Document 1 below). By arranging the exhaust port in this way, exhaust gas discharged from the fuel cell, or generated water generated by power generation, that is, electrochemical reaction between hydrogen and oxygen (hereinafter referred to as the exhaust gas or the generated water). Can also be discharged directly onto the road surface.

JP 2002-289237 A JP 2003-219512 A

  However, in the technique described in Patent Document 1, when a vehicle equipped with a fuel cell travels on a flooded road, the discharge port is blocked by water, earth and sand, etc. existing on the road surface, and exhaust is impossible. In some cases, the power generation by the fuel cell stops and the vehicle cannot run. Furthermore, there is a possibility that water, earth and sand, etc. flowing in from the discharge port reach the inside of the fuel cell through the piping and the like, leading to failure of the fuel cell.

  Such a problem is not limited to a vehicle equipped with a fuel cell, and is a common problem in various mobile objects that are equipped with a fuel cell and that travel on the road surface using the electric power generated by the fuel cell as a power source. is there. As such a moving body, an aircraft, a ship, etc. are mentioned other than the vehicle mentioned above, for example.

  The present invention has been made to solve the above-described problems, and in a mobile body equipped with a fuel cell, a discharge port for discharging the exhausted fluid discharged from the fuel cell to the outside of the mobile body is closed. It is an object of the present invention to provide a technique that enables traveling under a situation in which various obstructions that cause a problem exist around a moving body.

  In order to solve at least a part of the above-described problems, the present invention employs the following configuration. The moving body of the present invention is a moving body on which a fuel cell is mounted, and includes a discharge pipe for flowing a discharged fluid discharged from the fuel cell, and the discharge pipe sends the discharged fluid to the outside of the moving body. The present invention includes a plurality of discharge ports for discharging, and at least two of the plurality of discharge ports are respectively arranged at positions having different heights.

  In the present invention, the discharge pipe includes a plurality of discharge ports for discharging the discharge fluid discharged from the fuel cell to the outside of the moving body, and at least two of the plurality of discharge ports. However, since the heights are arranged at positions different from each other, the probability that these will be simultaneously occluded by the various occlusions described above, the plurality of outlets are arranged at the same height. It can be lower than the case. That is, for example, when the moving body of the present invention is traveling along a submerged channel, the discharge port disposed at a relatively low position such as the lower floor behind the moving body is blocked by water, earth or sand, etc. Even if it exists, it is possible to continue the power generation by the fuel cell, and to discharge the discharged fluid to the outside of the moving body by using the unoccluded discharge port arranged at a relatively high position. In addition, even when the discharge port arranged at a relatively high position is blocked by the above-mentioned falling objects, flying objects, etc. during normal traveling, the mobile body of the present invention generates power by the fuel cell. The discharge fluid can be discharged to the outside of the moving body by using an unblocked discharge port which is continuously performed and arranged at a relatively low position. Therefore, according to the present invention, it is possible to travel in a situation in which various obstructions that cause the discharge port to be obstructed exist around the moving body on which the fuel cell is mounted.

  In the above moving body, the discharge pipe can take various configurations. For example, the discharge pipe has a first pipe having a first discharge port at a terminal portion and a second discharge port at a terminal portion. A second pipe, and the second discharge port may be arranged at a higher position in the vertical direction than the first discharge port. By doing this, for example, even when the first discharge port arranged at a relatively low position is blocked by water, earth and sand, etc., while traveling on a submerged channel by the moving body of the present invention, Power generation by the fuel cell is continued, and the discharged fluid can be discharged to the outside of the moving body using the second non-blocked discharge port disposed at a relatively high position.

  As described above, the discharged fluid may contain generated water in addition to the exhaust gas. Therefore, it is preferable to discharge the discharged fluid from the first discharge port arranged at a relatively low position. The discharge fluid has a higher discharge efficiency than the discharge fluid discharged from the two discharge ports. Accordingly, in the moving body, in order to discharge the fluid discharged from the fuel cell to the outside of the moving body, the first discharge port is mainly used, and the second discharge port is used as an auxiliary. May be.

  In the above moving body, the first pipe and the second pipe may be provided independently, but the second pipe is branched from the first pipe and connected. It may be a thing. The first pipe has a high-order part formed so that the exhaust fluid flowing in the first pipe flows in a position higher than the first discharge port, and a part of the first pipe. And the second pipe is branched and connected from the high-order part of the first pipe or the upstream part in the flow direction of the discharged fluid from the high-order part. May be. By doing so, for example, when the mobile body of the present invention is traveling on a flooded channel, the water level on the road surface becomes higher than the height at which the first outlet is installed. However, until the height of the high portion is reached, water, earth and sand flowing in from the first discharge port are prevented from flowing into the fuel cell, and the second pipe and second The discharge fluid can be discharged using the discharge port.

  Note that in any one of the movable bodies in which the discharge pipe includes the first pipe and the second pipe, the inner diameter of the second pipe may be smaller than the inner diameter of the first pipe. . By carrying out like this, handling of the 2nd piping in a moving body can be made easy. Moreover, the space required for installing the second pipe can be reduced. Therefore, the enlargement of the moving body due to the provision of the second pipe can be suppressed.

  In the moving body in which the second pipe described above is branched and connected from the first pipe, the discharged fluid is supplied to the connection portion between the first pipe and the second pipe. There may be provided a switching section for switching between discharging from the discharge port or flowing through the second pipe and discharging from the second discharge port. In this way, for example, when the first discharge port is blocked or is likely to be blocked during traveling in the submerged channel by the moving body of the present invention, the switching fluid causes the discharge fluid to flow. Can flow from the first pipe to the second pipe and be discharged from the second outlet.

  In the moving body, the switching unit includes a pressure control mechanism for allowing the discharged fluid to flow into the second pipe when the pressure in the first pipe becomes a predetermined value or more. It may be. Note that the predetermined value related to the pressure in the first pipe is set to a value by which it can be determined that the first outlet is closed during power generation by the fuel cell. In this way, when the first discharge port is closed, the discharged fluid can be automatically discharged from the second discharge port without controlling the switching unit according to an instruction from the outside. Examples of the pressure control mechanism include a relief valve and an orifice.

  Further, in the moving body including the switching unit, a detection unit that detects the presence of an obstruction that closes the first discharge port around the moving body, and the discharge fluid as the switching unit. A switching valve for switching between discharging from the first discharge port or flowing through the second pipe and discharging from the second discharge port, and the presence of the obstruction detected by the detection unit And a valve control unit that controls the operation of the switching valve. In this way, the operation of the switching valve is controlled in accordance with the presence of the obstruction around the moving body, and the discharged fluid is discharged from the first discharge port or flows through the second pipe, It is possible to switch whether to discharge from the two discharge ports. As the detection unit, for example, a water level sensor, which will be described later, may be used, or the presence state of an obstruction on the road surface may be determined based on inundation information acquired through communication with an information center. Then, the road surface condition during traveling may be captured by a camera, and the captured image may be analyzed by image processing or the like to determine the presence state of the obstruction on the road surface.

  In the above moving body, the obstruction may be water present on the road surface, and the detection unit may include a water level sensor that detects a water level present on the road surface. In this way, the moving body of the present invention controls the operation of the switching valve in accordance with the water level existing on the road surface on which the moving body travels while traveling on the submerged channel, and the discharged fluid is allowed to flow through the first fluid. It is possible to switch between discharging from the discharge port or flowing through the second pipe and discharging from the second discharge port. In addition, as a water level sensor, various sensors, such as a float switch, an ultrasonic sensor, an electrostatic capacitance sensor, are applicable, for example.

  It is preferable that the moving body further includes an attenuation member for attenuating a undulation phenomenon on a water surface that is a detection target of the water level by the water level sensor. By doing so, it is possible to accurately detect the water level present on the road surface on which the moving body travels.

  In the moving body including a water level sensor as the detection unit, the valve control unit is configured such that when the water level detected by the water level sensor is equal to or higher than a predetermined value, the discharged fluid flows through the second pipe. The operation of the switching valve may be controlled. Note that the predetermined value related to the water level is set to a value by which it can be determined that water, earth and sand, or the like flows from the first outlet during the power generation by the fuel cell. By doing so, even when the moving body of the present invention travels along a submerged channel, water, earth and sand, or the like flows in from the first discharge port, or even under a situation where there is a risk of inflow, By controlling the operation, it is possible to prevent water or earth and sand flowing in from the first discharge port from flowing into the fuel cell and to prevent a failure of the fuel cell.

  In any one of the moving objects described above, the fuel cell may be arranged at a lower floor of the moving object. By so doing, when the moving body is, for example, a vehicle, the space under the floor of the vehicle can be used effectively. Further, by disposing the fuel cell in the lower part of the floor of the vehicle, the center of gravity of the vehicle can be lowered and the stability during traveling can be improved. In general, a vehicle equipped with a fuel cell is provided with a cooling device (radiator) for cooling cooling water for cooling the fuel cell. And this radiator is installed in the front of a vehicle in order to cool a cooling water using the driving | running | working wind at the time of driving | running | working of a vehicle. Therefore, by arranging the fuel cell in the lower floor of the vehicle, the space around the radiator can be widened as compared with the case where the fuel cell is arranged in the vicinity of the radiator. As a result, the heat dissipation efficiency of the radiator can be improved, and the air cooling efficiency of the cooling water can be improved.

  The present invention can be configured as an invention of a method for controlling a moving body in addition to the above-described structure as a moving body. Further, the present invention can be realized in various modes such as a computer program that realizes these, a recording medium that records the program, and a data signal that includes the program and is embodied in a carrier wave. In addition, in each aspect, it is possible to apply the various additional elements shown above.

  When the present invention is configured as a computer program or a recording medium on which the program is recorded, the entire program for controlling the operation of the moving object may be configured, or only the portion that performs the function of the present invention is configured. It may be a thing. The recording medium includes a flexible disk, a CD-ROM, a DVD-ROM, a magneto-optical disk, an IC card, a ROM cartridge, a punch card, a printed matter on which a code such as a barcode is printed, a computer internal storage device (RAM or Various types of computer-readable media such as a memory such as a ROM and an external storage device can be used.

Hereinafter, embodiments of the present invention will be described based on examples.
A. First embodiment:
A1. Configuration of the fuel cell system mounted on the vehicle:
FIG. 1 is an explanatory diagram showing a schematic configuration of a fuel cell system 100 mounted on a vehicle 1000 as an embodiment of the present invention. The vehicle 1000 is a so-called electric vehicle in which a motor is driven by the electric power generated by the fuel cell system 100 and the axle and wheels are rotated by the power. In the fuel cell system 100, when the driver operates the accelerator provided in the vehicle 1000, power generation is performed according to the operation amount detected by the accelerator opening sensor 80. The vehicle 1000 corresponds to a moving body in the present invention.

  The fuel cell (FC) stack 10 is a stacked body in which a plurality of cells that generate power by an electrochemical reaction between hydrogen and oxygen are stacked. Each cell has a configuration in which a hydrogen electrode (hereinafter referred to as an anode) and an oxygen electrode (hereinafter referred to as a cathode) are arranged (not shown) with an electrolyte membrane having proton conductivity interposed therebetween. In this embodiment, a solid polymer cell using a solid polymer membrane such as Nafion (registered trademark) is used as the electrolyte membrane. However, the present invention is not limited to this, and various types can be used.

  Hydrogen as fuel gas is supplied to the anode of the fuel cell stack 10 from a hydrogen tank 20 that stores high-pressure hydrogen via a pipe 23. Instead of the hydrogen tank 20, for example, a hydrogen generator that generates hydrogen by a reforming reaction using alcohol, hydrocarbon, aldehyde, or the like as a raw material may be used.

  The high pressure hydrogen stored in the hydrogen tank 20 is supplied to the anode of the fuel cell stack 10 after the pressure and supply amount are adjusted by a shut valve 21, a regulator 22, and the like provided at the outlet of the hydrogen tank 20. Exhaust gas from the anode (hereinafter referred to as anode off gas) is introduced into the gas-liquid separator 25 via the pipe 24. The gas-liquid separator 25 separates water contained in the anode off-gas from unconsumed hydrogen generated by the power generation by the fuel cell stack 10. The hydrogen separated by the gas-liquid separator 25 can be recirculated to the pipe 23 via the circulation pipe 26. A piping 28 is branched and connected between the gas-liquid separator 25 and the circulation pump 27 in the circulation piping 26, and a purge valve 29 is disposed in the piping 28. While the purge valve 29 is closed, the anode off-gas, that is, hydrogen separated by the gas-liquid separator 25 is circulated again to the fuel cell stack 10 via the circulation pipe 26. In this way, hydrogen can be used effectively. The pressure of the anode off gas is relatively low as a result of the consumption of hydrogen by power generation in the fuel cell stack 10, and therefore the anode off gas is added to the circulation pipe 26 when the anode off gas is recirculated. A circulation pump 27 for pressure is provided.

  During the recirculation of the anode off gas, hydrogen is consumed by power generation, while impurities other than hydrogen, for example, nitrogen permeated from the cathode side to the anode side through the electrolyte membrane remains without being consumed. The concentration of impurities inside increases gradually. At this time, when the purge valve 29 is opened, the anode off-gas is introduced into the diluter 50 via the pipe 28 and is diluted with the cathode off-gas in the diluter 50, as will be described later. It is discharged outside the system 100. By doing so, the concentration of impurities in the anode off-gas can be reduced. However, at this time, since hydrogen is also discharged at the same time, it is preferable to suppress the opening frequency of the purge valve 29 as much as possible from the viewpoint of improving fuel efficiency.

  The cathode of the fuel cell stack 10 is supplied with compressed air as an oxidant gas containing oxygen. Air is sucked from the air cleaner 30, compressed by the air compressor 32, and supplied from the pipe 34 to the cathode of the fuel cell stack 10. Note that a humidifier for humidifying the air supplied to the fuel cell stack 10 may be provided on the pipe 34 in order to maintain the electrolyte membrane of the fuel cell stack 10 in a wet state. Exhaust gas from the cathode (hereinafter referred to as cathode off gas) flows out to the pipe 36. The pipe 36 is provided with an air pressure regulating valve 35, and the air pressure in the fuel cell stack 10 can be controlled by controlling the air pressure regulating valve 35.

  The cathode offgas that has flowed into the pipe 36 and the anode offgas that has flowed into the pipe 28 when the purge valve 29 is opened are introduced into the diluter 50. The diluter 50 dilutes the concentration of hydrogen contained in the anode off gas by mixing the anode off gas and the cathode off gas. Exhaust gas discharged from the diluter 50 is discharged from the exhaust port at the end of the pipe 60 to the outside of the vehicle 1000 via the pipe 60 and the muffler 56.

  In the present embodiment, a switching unit 54 is provided between the diluter 50 and the muffler 56. Then, the pipe 62 connected to the pipe 60 by the switching unit 54 under a situation where the exhaust gas is not suitable for being discharged from the outlet of the end of the pipe 60 to the outside of the vehicle 1000 or cannot be discharged. It is also possible to discharge the vehicle 1000 from the discharge port at the end of the vehicle. Details of the switching unit 54 will be described later.

  Since the fuel cell stack 10 generates heat by the above-described electrochemical reaction, cooling water is also supplied to the fuel cell stack 10. The cooling water flows through the cooling water pipe 42 by the circulation pump 41, is cooled by the radiator 40, and is supplied to the fuel cell stack 10. In addition, as shown in the drawing, a bypass pipe 43 for circulating the cooling water without passing through the radiator 40 is connected to the pipe 42, and further, at one connection portion between the pipe 42 and the bypass pipe 43. Is provided with a three-way valve 44. Therefore, by switching the three-way valve 44, it is possible to circulate the cooling water through the pipe 42 and the bypass pipe 43 without passing through the radiator 40. Further, an ion exchanger 45 is connected to the pipe 42 via a pipe 46 as shown in the figure. The ion exchanger 45 removes various ions contained in the cooling water that cause an increase in the conductivity of the fuel cell stack 10.

  The operation of the fuel cell system 100 is controlled by the control unit 70. The control unit 70 is configured as a microcomputer including a CPU, a RAM, and a ROM therein, and controls the operation of the system such as driving various valves and pumps according to a program stored in the ROM. The control unit 70 corresponds to the valve control unit in the present invention.

  Although not shown, in the vehicle 1000 according to the present embodiment, the fuel cell stack 10 is housed in a stack case and installed at the lower floor of the vehicle 1000. Further, the diluter 50, the gas-liquid separator 25, the switching unit 54, the muffler 56, and the pipes connecting them are also installed in the lower floor of the vehicle 1000. Further, the hydrogen tank 20 is installed in the lower part of the rear seat of the vehicle 1000. By doing so, the space under the floor of the vehicle 1000 can be used effectively. Further, by arranging the fuel cell stack 10 and the like in the lower part of the floor of the vehicle 1000, the center of gravity of the vehicle 1000 can be lowered and the stability during travel can be improved.

  Further, the radiator 40, the circulation pump 41, the ion exchanger 45, the control unit 70, and the like are installed in a space in front of the vehicle 1000. Therefore, as compared with the case where the fuel cell stack 10 and the like are arranged in the vicinity of the radiator 40, the space around the radiator 40 can be widened. As a result, the heat dissipation efficiency of the radiator 40 can be improved, and the cooling efficiency of cooling water can be improved.

A2. Configuration of switching unit:
FIG. 2 is an explanatory diagram showing a schematic configuration of the switching unit 54 of the first embodiment. Here, for simplification of illustration, only a part of the fuel cell system 100 (see FIG. 1) mounted on the vehicle 1000 is illustrated. As shown in the drawing, in this embodiment, the pipe 60 is provided with a U-shaped tube 60u having a convex shape upward in the vertical direction, and a discharge port 60o is provided at the end portion thereof. Yes. The discharge port 60o is arranged in the lower floor behind the vehicle 1000. The piping 60 and the U-shaped tube 60u correspond to the first piping in the present invention, and the U-shaped tube 60u corresponds to the high portion in the present invention. Further, the discharge port 60o corresponds to the first discharge port in the present invention.

  A pipe 62 is branched and connected to the top of the U-shaped tube 60u. The pipe 62 extends to the upper part of the trunk room along the inner side surface of the body of the vehicle 1000, and a discharge port 62o is provided at the terminal end. That is, the discharge port 62o is arranged at a position higher than the discharge port 60o. The pipe 62 corresponds to the second pipe in the present invention, and the discharge port 62o corresponds to the second discharge port in the present invention.

  The piping 62 is provided with a relief valve 54Vr. The relief valve 54Vr is closed at normal times, that is, when the pressure in the U-shaped tube 60u is relatively low, and automatically when the pressure in the U-shaped tube 60u exceeds a predetermined value. Open. The predetermined value related to the pressure in the U-shaped tube 60u is set to a value by which it can be determined that the discharge port 60o is closed during power generation by the fuel cell stack 10. The relief valve 54Vr corresponds to the pressure control mechanism in the present invention.

  In the present embodiment, although not shown, the inner diameter of the pipe 62 is set to be sufficiently smaller than the inner diameter of the pipe 60. Therefore, the handling of the piping 62 in the vehicle 1000 can be facilitated. Further, the space required for installing the pipe 62 can be reduced. Therefore, it is possible to suppress an increase in size of the vehicle 1000 due to the provision of the pipe 62 and a decrease in the living space in the vehicle.

  In the vehicle 1000 having the switching unit 54 described above, when traveling on a submerged channel, and the water level of the water existing on the road surface RS is lower than the height h1 from the road surface RS to the upper part of the discharge port 60o, Alternatively, when traveling on a normal dry road surface RS, the pressure in the U-shaped tube 60u is relatively low, so the relief valve 54Vr is closed, and the exhaust gas discharged from the fuel cell stack 10 is The air is discharged from the discharge port 60o to the outside of the vehicle 1000.

  On the other hand, when the vehicle 1000 travels on a submerged road and the water level on the road surface RS is higher than the height h1 from the road surface RS to the upper part of the discharge port 60o, the discharge port 60o. Is blocked by water, earth and sand, etc., and the pressure in the U-shaped pipe 60u increases, so that the relief valve 54Vr automatically opens, and the exhaust gas discharged from the fuel cell stack 10 flows through the pipe 62. Then, the fuel is discharged to the outside of the vehicle 1000 through the discharge port 62o provided at the end thereof. In addition, water and earth and sand are prevented from flowing upstream of the U-shaped pipe 60u until the water level on the road surface RS exceeds the height h2 from the road surface RS to the top of the U-shaped pipe 60u. can do.

  In addition, after the vehicle 1000 passes through the submerged channel, when water or earth or sand that has blocked the outlet 60o is removed by the back pressure of the exhaust gas, the pressure in the U-shaped pipe 60u decreases. The relief valve 54Vr is automatically closed.

A3. Effects of Comparative Example and First Example:
As a comparative example of the first embodiment, the technique described in Patent Document 2 described above is given. Patent Document 2 describes a technique in which a discharge port (gas discharge port) is arranged in a rectifying structure (air spoiler) installed at a rear end of a vehicle body in a vehicle equipped with a fuel cell. . According to this technology, since the discharge port is arranged at a position higher than the lower floor of the vehicle main body, even when traveling on a flooded road where the water level present on the road surface is relatively high, The vehicle can travel without the discharge port being blocked by existing water or earth and sand.

  However, the obstruction | occlusion thing which obstruct | occludes a discharge port is not restricted to the water, earth and sand, etc. which exist on a road surface. Examples of such obstructions include falling objects from the sky, flying objects, and floating objects. And in the technique described in the above-mentioned patent document 2, since the discharge port is arranged in the rectifying structure installed at a relatively high position of the vehicle main body, the discharge port is provided in the lower floor behind the vehicle main body. Compared with the case where it arrange | positions, possibility that the discharge port will be obstruct | occluded with the fallen object mentioned above, a flying object, etc. was high. And when the discharge port arranged in this rectifying structure is closed, it becomes impossible to exhaust, similarly to the case where the discharge port is closed by water or earth and sand, power generation by the fuel cell is stopped, In some cases, it was impossible to run.

  On the other hand, according to the vehicle 1000 of the first embodiment, the two exhaust ports 60o and 62o are provided as exhaust ports for exhausting the exhaust gas discharged from the fuel cell stack 10 to the outside of the vehicle 1000. Since the discharge port 62o is arranged at a position higher than the discharge port 60o, the discharge port 60o arranged at a relatively low position in the lower floor at the rear of the vehicle 1000 during traveling on the submerged channel is provided. Even when blocked by water, earth or sand, etc., the power generation by the fuel cell stack 10 is continued, and the unoccluded outlet 62o arranged at a relatively high position in the upper part of the trunk room is used. The exhaust gas can be discharged to the outside of the vehicle 1000. In addition, for example, while traveling on a normal road surface that is not a submerged channel, the discharge port 62o disposed at a relatively high position in the upper part of the trunk room is caused by falling objects or flying objects from the sky as described above. Even when the fuel cell stack 10 is closed, the fuel cell stack 10 continues to generate power, and is discharged using the non-blocked discharge port 60o disposed at a relatively low position at the lower bottom of the floor behind the vehicle 1000. Gas can be discharged to the outside of the vehicle 1000.

B. Second embodiment:
The vehicle 1000 of the second embodiment is the same as the vehicle 1000 of the first embodiment except for the switching unit in the fuel cell system 100. Hereinafter, the switching unit 54A of the second embodiment will be described.

B1. Configuration of switching unit:
FIG. 3 is an explanatory diagram showing a schematic configuration of the switching unit 54A of the second embodiment. As shown in the figure, also in the present embodiment, as in the first embodiment described above, the pipe 60 is provided with a U-shaped tube 60u having a convex shape upward in the vertical direction, A discharge port 60o is provided at the end portion. Moreover, the discharge port 60o is arrange | positioned at the floor lower part of the back of the vehicle 1000 (refer FIG. 2).

  In this embodiment, unlike the first embodiment, a pipe 62 is branched and connected to the pipe 60 on the upstream side of the U-shaped pipe 60u. The pipe 62 extends to the rear end of the roof along the inner surface of the body (not shown) of the vehicle 1000, and a discharge port 62o is provided at the end. That is, the discharge port 62o is arranged at a position higher than the discharge port 60o. Further, the inner diameter of the pipe 62 is sufficiently smaller than the inner diameter of the pipe 60.

  In the present embodiment, the piping 62 is provided with an electrically driven valve 54V instead of the relief valve 54Vr in the first embodiment. The valve 54V is always closed during normal driving, that is, when driving on a road surface other than the submerged channel, and exhaust gas discharged from the fuel cell stack 10 is discharged from the exhaust port 60o to the outside of the vehicle 1000. Discharged. The U-shaped tube 60u is provided with a pressure sensor 82 for detecting the pressure in the U-shaped tube 60u. Then, the control unit 70 controls the opening / closing operation of the valve 54 </ b> V according to the output of the pressure sensor 82. The valve 54V corresponds to the switching valve in the present invention. The pressure sensor 82 corresponds to the detection unit in the present invention.

B2. Valve control processing:
FIG. 4 is a flowchart showing the flow of the valve control process for the valve 54V in the present embodiment. This process is a process executed by the CPU of the control unit 70 while the vehicle 1000 is traveling.

  First, the CPU detects the pressure Po in the U-shaped tube 60u by the pressure sensor 82 (step S100), and determines whether or not the pressure Po is equal to or higher than a predetermined threshold Pth (step S110). This threshold value Pth is set to a value by which it can be determined that the discharge port 60o is closed during power generation by the fuel cell stack 10.

  When the pressure Po in the U-shaped tube 60u is less than the threshold value Pth (step S110: NO), the CPU determines that the discharge port 60o is not closed and returns to step S100.

  On the other hand, when the pressure Po in the U-shaped tube 60u is equal to or higher than the threshold value Pth (step S110: YES), the CPU determines that the discharge port 60o is blocked by the obstruction and opens the valve 54V. (Step S120), the exhaust gas discharged from the fuel cell stack 10 is caused to flow through the pipe 62 and discharged from the discharge port 62o to the outside of the vehicle 1000.

  Then, the valve control process ends. After the valve control process, the CPU further detects the pressure Po in the U-shaped tube 60u with the pressure sensor 82, and when the pressure Po in the U-shaped tube 60u drops below the threshold value Pth, the CPU It may be determined that the closing of the outlet 60o has been resolved, and a process of closing the valve 54V may be performed.

  The vehicle 1000 of the second embodiment described above is also provided with two discharge ports 60o and 62o as discharge ports for discharging the exhaust gas discharged from the fuel cell stack 10 to the outside of the vehicle 1000. Since the discharge port 62o is disposed at a position higher than the discharge port 60o, the discharge port 60o disposed at a relatively low position is blocked by water, earth or sand, etc. while traveling in the submerged channel. Even in this case, power generation by the fuel cell stack 10 can be continued, and exhaust gas can be discharged to the outside of the vehicle 1000 using the non-blocked discharge port 62o disposed at a relatively high position. .

C. Third embodiment:
In the first embodiment and the second embodiment described above, the exhaust port used for discharging the exhaust gas discharged from the fuel cell to the outside of the vehicle 1000 according to the pressure in the U-shaped tube 60u, Switching is performed automatically or by valve control. In the present embodiment, the discharge port used for discharging the exhaust gas discharged from the fuel cell to the outside of the vehicle 1000 is switched in accordance with the water level present on the road surface RS. In this embodiment, as an example, the gas-liquid separator 25 is provided with a water level sensor for detecting the water level of the water present on the road surface RS. The vehicle 1000 according to the third embodiment is the same as the vehicle 1000 according to the second embodiment except that the fuel cell system 100 includes a water level sensor and the switching unit in the fuel cell system 100.

C1. Gas-liquid separator (water level sensor):
FIG. 5 is an explanatory diagram showing a schematic configuration of the gas-liquid separator 25. As described above, the gas-liquid separator 25 is a device that separates and removes water contained in the exhaust gas discharged from the diluter 50. The separated water is discharged from a drain portion 25d provided at the lower part of the gas-liquid separator 25. In this embodiment, as shown in the figure, a water level sensor 84 is provided in the drain portion 25d.

  By doing so, the water level WS1 is outside the drain part 25d of the gas-liquid separator 25 while the water level of the water existing on the road surface RS is traveling higher than the lower part of the drain part 25d by the vehicle 1000. Even in the case where the undulation phenomenon occurs, the undulation phenomenon of the water surface WS2 can be attenuated in the drain portion 25d. Therefore, the water level sensor 84 can accurately detect the water level present on the road surface RS. The drain portion 25d corresponds to the damping member in the present invention.

C2. Configuration of switching unit:
FIG. 6 is an explanatory diagram showing a schematic configuration of the switching unit 54B of the third embodiment. As shown in the figure, in this embodiment, the pipe 60 does not include a U-shaped tube 60u, unlike the first and second embodiments. However, the discharge port 60o is arranged in the lower floor behind the vehicle 1000 (not shown) as in the first and second embodiments.

  A pipe 62 is branched and connected to the pipe 60, and the pipe 62 extends to the rear end of the roof along the inner surface of the body (not shown) of the vehicle 1000, as in the second embodiment. A discharge port 62o is provided at the end portion. That is, the discharge port 62o is arranged at a position higher than the discharge port 60o. Further, the inner diameter of the pipe 62 is sufficiently smaller than the inner diameter of the pipe 60.

  In the present embodiment, a three-way valve 54Va is disposed at a connection portion between the pipe 60 and the pipe 62. Then, by controlling the operation of the three-way valve 54Va, the exhaust gas discharged from the fuel cell stack 10 is discharged from the discharge port 60o to the outside of the vehicle 1000, or flows into the pipe 62 and flows from the discharge port 62o to the vehicle 1000. It is possible to switch whether to discharge outside. The three-way valve 54Va corresponds to the switching valve in the present invention. Operation control of the three-way valve 54Va is performed by the control unit 70 in accordance with the output of the water level sensor 84 provided in the gas-liquid separator 25 described above.

C3. Valve control processing:
FIG. 7 is a flowchart showing a flow of valve control processing of the three-way valve 54Va in the present embodiment. This process is a process executed by the CPU of the control unit 70 while the vehicle 1000 is traveling. At the start of this process, the communication state of the three-way valve 54Va is switched so that the exhaust gas discharged from the fuel cell stack 10 is discharged from the discharge port 60o to the outside of the vehicle 1000.

  First, the CPU detects the water level Hw in the gas-liquid separator 25, that is, the water level present on the road surface RS by the water level sensor 84 (step S200), and the water level Hw is equal to or higher than a predetermined threshold value Hth. It is determined whether or not there is (step S210). The threshold value Hth is set to a value by which it can be determined that the discharge port 60o is closed during power generation by the fuel cell stack 10.

  When the water level Hw in the gas-liquid separator 25 is less than the threshold value Hth (step S210: NO), the CPU determines that the discharge port 60o is not blocked and returns to step S200.

  On the other hand, when the water level Hw in the gas-liquid separator 25 is equal to or higher than the threshold value Hth (step S210: YES), the CPU determines that the discharge port 60o is blocked by the obstruction, and the three-way valve 54Va The communication state is switched (step S220), and the exhaust gas discharged from the fuel cell stack 10 flows through the pipe 62 and is discharged from the exhaust port 62o to the outside of the vehicle 1000.

  Then, the valve control process ends. Note that the CPU further detects the water level Hw in the gas-liquid separator 25 by the water level sensor 84 after this valve control processing, and the water level Hw in the gas-liquid separator 25 falls below the threshold value Hth. Therefore, it is determined that the blockage of the discharge port 60o has been eliminated, and a process of switching the communication state of the three-way valve 54Va is performed so that the exhaust gas discharged from the fuel cell stack 10 is discharged from the discharge port 60o. May be.

  The vehicle 1000 of the third embodiment described above is also provided with two discharge ports 60o and 62o as discharge ports for discharging the exhaust gas discharged from the fuel cell stack 10 to the outside of the vehicle 1000. Since the discharge port 62o is disposed at a position higher than the discharge port 60o, the discharge port 60o disposed at a relatively low position is blocked by water, earth or sand, etc. while traveling in the submerged channel. Even in this case, power generation by the fuel cell stack 10 can be continued, and exhaust gas can be discharged to the outside of the vehicle 1000 using the non-blocked discharge port 62o disposed at a relatively high position. .

D. Variations:
As mentioned above, although several embodiment of this invention was described, this invention is not limited to such embodiment at all, and implementation in various aspects is possible within the range which does not deviate from the summary. It is. For example, the following modifications are possible.

D1. Modification 1:
In the first embodiment, the relief valve 54Vr is disposed in the pipe 62, but the present invention is not limited to this. For example, an orifice may be provided in the pipe 62 instead of the relief valve 54Vr. However, when an orifice is provided in the pipe 62, the exhaust gas discharged from the fuel cell stack 10 is always discharged outside the vehicle 1000 also from the discharge port 62o.

  In the first embodiment, the pipe 62 is connected to the top of the U-shaped tube 60u. However, as in the second embodiment, the pipe 62 is connected to the upstream side of the U-shaped tube 60u. Also good.

D2. Modification 2:
In the second embodiment, the valve 54V is opened when the pressure in the U-shaped tube 60u detected by the pressure sensor 82 exceeds a predetermined value. However, the present invention is not limited to this. Absent. For example, as in the third embodiment, a water level sensor capable of detecting the water level present on the road surface RS is provided at any position of the vehicle 1000, and the water level detected by the water level sensor is equal to or greater than a predetermined value. At this time, the valve 54V may be opened.

D3. Modification 3:
In the third embodiment, the water level sensor 84 is provided in the gas-liquid separator 25, but the present invention is not limited to this.

  FIG. 8 is an explanatory view showing the arrangement of a water level sensor 84 as a modified example. In the present modification, a sensor box 84B having a plurality of through holes is formed around the bottom of the side surface of the stack case 12 in which the fuel cell stack 10 is accommodated. A sensor 84 is installed.

  Also by doing this, the water level of the water surface WS1 on the road surface RS is running outside the sensor box 84B while the water level on the road surface RS is running higher than the lowermost part of the stack case 12 by the vehicle 1000. Even if it occurs, the wave level phenomenon of the water surface WS2 can be attenuated in the sensor box 84B, so that the water level sensor 84 can accurately detect the water level present on the road surface RS. it can. The sensor box 84B corresponds to a damping member in the present invention.

  In this modification, the sensor box 84B is provided, but the sensor box 84B may not be provided. In the third embodiment and the modified example of the third embodiment, a water level sensor that detects water level by contact with water is used, but an ultrasonic sensor or the like is not in contact with water. You may make it use the water level sensor which detects the distance with the water surface. Further, the water level sensor 84 may be provided in another part of the vehicle 1000.

D4. Modification 4:
In the first to third embodiments, the pipe 62 is connected to the pipe 60, but the present invention is not limited to this. In general, according to the present invention, a plurality of discharge pipes for discharging exhaust fluid (exhaust gas or generated water) discharged from a fuel cell (fuel cell stack 10) to the outside of a mobile body (for example, a vehicle 1000) are provided. The discharge port is provided, and at least two of the plurality of discharge ports may be arranged at positions where the heights of the main body of the movable body are different from each other.

  FIG. 9 is an explanatory view showing the arrangement of the piping 60 and the piping 62 as a modification. As shown in the drawing, in this modification, the pipe 62 is not connected to the pipe 60 and is installed in the vehicle 1000 independently. The pipe 60 and the pipe 62 are provided with a valve 54V1 and a valve 54V2, respectively. These valves 54V1 and 54V2 correspond to the switching unit in the present invention. And control of operation | movement of valve | bulb 54V1, 54V2 is performed by the control unit 70 according to the output of the water level sensor 84 demonstrated previously in 3rd Example.

  In this modification as well, the discharge port 60o is disposed in the lower floor at the rear of the vehicle 1000, and the discharge port 62o is disposed at the rear end of the roof of the vehicle 1000.

  FIG. 10 is an explanatory diagram showing the flow of valve control in this modification. This process is a process executed by the CPU of the control unit 70 while the vehicle 1000 is traveling. In this modification, at the start of this process, the valve 54V1 is opened and the valve 54V2 is closed. Therefore, during normal travel, the exhaust gas discharged from the fuel cell stack 10 is discharged outside the vehicle 1000 from the discharge port 60o.

  First, the CPU detects the water level Hw in the gas-liquid separator 25, that is, the water level present on the road surface RS by the water level sensor 84 (step S300), and the water level Hw is equal to or higher than a predetermined threshold value Htha. It is determined whether or not there is (step S310). The threshold value Htha is set to a value at which it can be determined that water, earth and sand, etc. may flow from the outlet 60o during power generation by the fuel cell stack 10. Therefore, the threshold value Htha is set to a value smaller than the threshold value Hth in the third embodiment.

  When the water level Hw in the gas-liquid separator 25 is less than the threshold value Htha (step S310: NO), the CPU determines that there is no risk of water, earth and sand flowing in from the outlet 60o, and the step Return to S300.

  On the other hand, when the water level Hw in the gas-liquid separator 25 is equal to or higher than the threshold value Htha (step S310: YES), the CPU determines that there is a possibility that water, earth and sand, etc. may flow from the outlet 60o. Then, the valve 54V1 disposed in the pipe 60 is closed and the valve 54V2 disposed in the pipe 62 is opened (step S320), and the exhaust gas discharged from the fuel cell stack 10 is caused to flow to the pipe 62. , And discharged from the discharge port 62o to the outside of the vehicle 1000.

  Then, the valve control process ends. The CPU further detects the water level Hw in the gas-liquid separator 25 by the water level sensor 84 after the valve control process, and the water level Hw in the gas-liquid separator 25 falls below the threshold value Htha. The communication state of the three-way valve 54Va is determined such that the exhaust gas discharged from the fuel cell stack 10 is discharged from the discharge port 60o by determining that there is no risk of water, earth and sand flowing in from the discharge port 60o. You may make it perform the process which switches.

  According to the vehicle 1000 of this modification described above, the two exhaust ports 60o and 62o are provided as exhaust ports for exhausting the exhaust gas discharged from the fuel cell stack 10 to the outside of the vehicle 1000. Since the discharge port 62o is disposed at a position higher than the discharge port 60o, there is a possibility that water, earth and sand, etc. may flow from the discharge port 60o disposed at a relatively low position while traveling on the submerged channel. In this case, the valve 54V1 is closed to prevent inflow of water, earth and sand, etc. from the discharge port 60o, and the power generation by the fuel cell stack 10 is continuously performed. Exhaust gas can be discharged to the outside of the vehicle 1000 using the exhaust port 62o that is not.

  In the valve control process in the above modification, the valve 54V2 is closed during normal traveling, but may be opened.

  In the above modification, the valve 54V1 is disposed in the pipe 60. Instead, the U-shaped pipe 60u described in the first embodiment is provided in a part of the pipe 60 instead. Also good. By doing so, even when water, earth and sand, etc. flow from the discharge port 60o while traveling on the flooded channel by the vehicle 1000, the water level existing on the road surface RS is changed from the road surface RS to the U-shaped pipe 60u. Until the height to the top is exceeded, water, earth and sand, etc. can be prevented from flowing into the upstream side of the U-shaped tube 60u.

  In the above modification, the valve 54V2 is disposed in the pipe 62. However, the valve 54V2 may not be disposed in the pipe 62.

D5. Modification 5:
In the said Example and modification, although the internal diameter of the piping 62 shall be smaller than the internal diameter of the piping 60, this invention is not limited to this. For example, the inner diameter of the pipe 60 and the inner diameter of the pipe 62 may be the same.

D6. Modification 6:
In the second and third embodiments and the modified examples, the discharge port 62o is arranged at the rear end of the roof of the vehicle 1000, but the present invention is not limited to this. The discharge port 62o only needs to be arranged at a position higher than the discharge port 60o. It is good also as what to do.

D7. Modification 7:
In the above-described embodiment and the modification, two pipes, that is, the pipe 60 and the pipe 62 are provided as exhaust pipes for exhausting the exhaust gas discharged from the fuel cell stack 10 to the outside of the vehicle 1000. However, the present invention is not limited to this. Three or more pipes may be provided as the discharge pipe. By doing so, any of the plurality of outlets is not limited to obstructions, i.e., water or earth and sand on the submerged channel, but obstructed by falling objects, flying objects, floating objects, etc. Even in such a case, the exhaust fluid discharged from the fuel cell can be discharged from another discharge port, and the vehicle can travel.

D8. Modification 8:
In the above embodiment, the fuel cell stack 10 is installed in the lower floor of the vehicle 1000, but the present invention is not limited to this. For example, it may be installed at another position such as a space in front of the vehicle 1000.

D9. Modification 9:
Although the case where the present invention is applied to the vehicle 1000 has been described in the above embodiment, the present invention is not limited to this. The present invention can be applied to various mobile bodies that are equipped with a fuel cell and move using the power generated by the fuel cell as a power source.

It is explanatory drawing which shows schematic structure of the fuel cell system 100 mounted in the vehicle 1000 as one Example of this invention. It is explanatory drawing which shows schematic structure of the switching part 54 of 1st Example. It is explanatory drawing which shows schematic structure of the switching part 54A of 2nd Example. It is a flowchart which shows the flow of the valve control processing of the valve 54V. 3 is an explanatory diagram showing a schematic configuration of a gas-liquid separator 25. FIG. It is explanatory drawing which shows schematic structure of the switching part 54B of 3rd Example. It is a flowchart which shows the flow of the valve control processing of the three-way valve 54Va. It is explanatory drawing which shows arrangement | positioning of the water level sensor 84 as a modification. It is explanatory drawing which shows arrangement | positioning of the piping 60 and the piping 62 as a modification. It is explanatory drawing which shows the flow of the valve control in a modification.

Explanation of symbols

1000 ... Vehicle 100 ... Fuel cell system 10 ... Fuel cell stack 12 ... Stack case 20 ... Hydrogen tank 21 ... Shut valve 22 ... Regulator 23, 24 ... Piping 25 ... Gas-liquid separator 25d ... Drain part 26 ... Circulating piping 27 ... Circulating pump 28 ... Piping 29 ... Purge valve 30 ... Air cleaner 32 ... Air compressor 34,36 ... Piping 35 ... Air pressure regulator 40 ... Radiator 41 ... Circulating pump 42 ... Piping 43 ... Bypass piping 44 ... Three way valve 45 ... Ion exchanger 46 ... Piping 50 ... Diluter 54, 54A, 54B ... Switching part 54V, 54V1, 54V2 ... Valve 54Va ... Three-way valve 54Vr ... Relief valve 56 ... Muffler 60 ... Piping 60o. ..Discharge port 60u ... U-shaped pipe 62 ... Piping 62o ... Discharge port 70 ... Control unit 80 ... Accelerator opening sensor 2 ... pressure sensor 84 ... the water level sensor 84B ... sensor box

Claims (9)

A mobile body equipped with a fuel cell,
A discharge pipe for flowing the exhaust fluid discharged from the fuel cell;
The discharge pipe includes a plurality of discharge ports for discharging the discharged fluid to the outside of the moving body,
The discharge pipe includes a first pipe having a first discharge port at a terminal end, and a second pipe having a second discharge port at a terminal end,
The second outlet is disposed at a position higher in the vertical direction than the first outlet,
The first pipe has, as a part of the first pipe, a high-order part formed so that the exhaust fluid flowing in the first pipe flows in a position higher than the first discharge port. And
The second pipe is a movable body that is branched and connected from the high-order part in the first pipe or from the upstream part in the flow direction of the exhaust fluid from the high-order part . 2. The moving body according to claim 1 , wherein an inner diameter of the second pipe is smaller than an inner diameter of the first pipe. The moving body according to claim 1 or 2 ,
The discharged fluid is discharged from the first discharge port to the connecting portion between the first pipe and the second pipe, or is allowed to flow through the second pipe and discharged from the second discharge port. A moving body comprising a switching unit that switches between the two. The moving body according to claim 3 ,
A moving body provided with a pressure control mechanism for causing the exhaust fluid to flow to the second pipe when the pressure in the first pipe becomes a predetermined value or more as the switching unit. The mobile body according to claim 3 , further comprising:
A detection unit that detects the presence of an obstruction that closes the first discharge port around the moving body;
As the switching unit, a switching valve that switches whether the discharged fluid is discharged from the first discharge port or flows through the second pipe and is discharged from the second discharge port;
A valve control unit that controls the operation of the switching valve according to the presence of the obstruction detected by the detection unit;
A moving object comprising: The moving body according to claim 5 , wherein the obstruction is water existing on the road surface, and the detection unit includes a water level sensor that detects a water level of the water existing on the road surface. . The mobile body according to claim 6 , further comprising:
A moving body comprising an attenuation member for attenuating a undulation phenomenon on a water surface to be detected by the water level sensor. The moving body according to claim 6 or 7 ,
The said valve control part is a moving body which controls operation | movement of the said switching valve so that the said exhausted fluid may flow into the said 2nd piping, when the water level detected by the said water level sensor is more than predetermined value. A mobile body according to any one of claims 1 to 8, wherein the fuel cell is arranged under the floor of the movable body, the moving body.

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